1. Field of the Invention
The present invention relates to an optical low-noise block down-converter and satellite television system, and more particularly, to an optical low-noise block down-converter and satellite television system capable of draining out part of the radio satellite signals to convert into a legacy electrical signal for improving an installation efficiency for the satellite television system.
2. Description of the Prior Art
An optical Low-Noise Block Down-converter (hereinafter called optical-LNB) is an advanced component for a satellite television system. Optical communication has advantages such as a wide bandwidth, a low signal loss for long distance transmission, an immunity from electromagnetic interference, and can be equipped with a passive optical splitter for transmitting multiple optical signals to multiple users simultaneously, which may overcome a disadvantage of great signal loss due to long distance transmission for a traditional cable, e.g. RG-6 cable.
In general, a traditional optical-LNB includes an F-connector for receiving an input power and a FC-connector for outputting an optical signal. However, the traditional optical-LNB does not have an output port for the radio satellite signal, i.e. an electrical signal, to support a Legacy operating mode. Hence, for positioning and aligning an antenna dish with a satellite, staff of a satellite television system operator may utilize a multiple dwelling unit to convert the optical signal into an electrical signal and utilize a signal demodulator, e.g. a set-up box, to demodulate the electrical signal. As a result, the staff may determine whether an installation of the antenna dish succeeded according to the demodulated electrical signal. Besides, the antenna dish and the optical-LNB are usually installed on a roof or an exterior wall of a building where power sockets or power source may not be available. Thus, the staff may have to use power from an interior of the building for powering the multiple dwelling unit and the demodulator. Such environmental disadvantages may prolong a time for positioning and aligning the antenna dish with the satellite and increase difficulties in installation of the satellite television system.
Therefore, how to directly drain out the satellite signals to convert into the electrical signal to support the legacy operating mode without affecting the standard installation of the satellite television system for speeding up the installation has become a main topic of the industry.